ammeter to voltmeter conversion.
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ammeter to voltmeter conversion.
I have a 1974 coupe that I tried to convert the ammeter to voltmeter. I have the cluster out to replace the bezel and installed the voltmeter. I'm running power from the pink wire on the water temp gauge to the + on the voltmeter. Where do I attach GRN? I tried using the black wire on the temperature gauge but it just blows the ignition fuse. Solution?? Thanks
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From: New Or-leens Loo-z-anna
Try ground the black wire to the metal gauge housing.
you a 12V wire fron the amp gauge
Make sure the housing is grounded.
Yiu nay need to reposition the needle to show 12V with the key ON.
you a 12V wire fron the amp gauge
Make sure the housing is grounded.
Yiu nay need to reposition the needle to show 12V with the key ON.
Drifting
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From: Loud, Raw and Dangerous 1968 327 4S in Southern California
If the meter is the typical mechanical "gavanometer" type it is a wire coil wound on the needle moving in a permanent magnet field. It may still need a series resistance to operate correctly as a voltmeter and not short out that pink wire B+ connection which blows the gauges/ignition fuse (could also damage the meter). The temp gauge black wire is to the ground of the car and should have been a good battery B- voltage connection.
I would recommend first measuring the meter's resistance with an ohmmeter to get a feel of the meters design or a possible short, and what current actually was being drawn (divide value into 12).
I would recommend first measuring the meter's resistance with an ohmmeter to get a feel of the meters design or a possible short, and what current actually was being drawn (divide value into 12).
Last edited by Redvette2; Oct 28, 2024 at 11:35 AM. Reason: As Richard454 said...possible short!
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The black wire on the water gauge is a ground-
You can try grounding directly to the gauge or console ground-
But just a guess- it will pop a fuse too. If so look over the volt gauge- I have seen several that the + terminal is
not isolated- loose plastic washer from the gauges case- causing a short.
Richard
You can try grounding directly to the gauge or console ground-
But just a guess- it will pop a fuse too. If so look over the volt gauge- I have seen several that the + terminal is
not isolated- loose plastic washer from the gauges case- causing a short.
Richard
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This how I wired mine. Pink is 12 volts black is the ground. Make sure your gauge wiring diagram shows where they are located. I isolated the stud on the left from the housing because I believe it to be hot with 12 volts.
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The metal chassis the gauges bolt to is grounded via the water temperature gauge According to the service manual I was able to get my hands on.
So I connected my pink wire from the 24 volt side of my new voltmeter to the pink on the water temperature gauge and just bolted the gauge to the chassis with the ground stud on the gauge. Works and no blown fuse.
So I connected my pink wire from the 24 volt side of my new voltmeter to the pink on the water temperature gauge and just bolted the gauge to the chassis with the ground stud on the gauge. Works and no blown fuse.
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From: Loud, Raw and Dangerous 1968 327 4S in Southern California
"Can you install a Voltmeter in the place of an Ammeter? To measure flow, Ammeter gauges connect with both positive wires. Voltmeter gauges measure volts with a positive to ground connection. A Voltmeter can be installed in a Corvette with a factory Ammeter gauge, BUT a new ground wire MUST be installed. Otherwise, your new Voltmeter will immediately short out. Incorrectly installed Voltmeters are not eligible for return."
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The 2 wires connected to the ammeter are black and black with a white line...both carry 12 vdc....use one of those as your power source for your voltmeter, tape the other on off and run a seperate ground to the birdcage under the dash or to any ground you like
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